Fuse



NQV. 11, 1941. G TOWNER 7 2,262,068

FUSE

Filed April 6, 1958 Inventor Harald BJPuwnEr Patented Nov. 11, 1941UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, asamended April 30, 1928; 370 G. 757) 1 Claim.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes, without the payment to me ofany royalty thereon.

This invention relates in general to a fuse and more particularly it hasreference to means for rotatably connecting the base and setting cap ofa time fuse.

In fuses wherein the cap is to be rotatable with respect to the base ithas been the usual practice to connect these units by some form ofcoupling ring.

The purpose of this invention is to provide a simple and effectiveconnection which will permit relative rotation of the cap and base toset the timing mechanism of the fuse and which will prevent theirderangement under the influence of centrifugal force during flight.

To these and other ends, the invention consists in the construction,arrangement and. combination of elements described hereinafter andpointed out in the claim forming a part of this specification.

A practical embodiment of the invention is illustrated in theaccompanying drawing, wherein:

Fig. 1 is a longitudinalsectional view of a fuse casing whose units areheld in assembly by the improved coupling means;

Fig. 2 is a sectional view on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged sectional view on the line 3--3 of Fig. 1.

Referring to the drawing by characters of reference there is shown afuse casing comprising a base 5 and a rotatable setting cap 6. The baseis formed with a reduced upper part I for receiving the lower end of thecap which rests upon an annular seat 8 established in the base.

The lower end of the cap is provided internally with a radialcircumferential or annular groove 9 which, when the cap is resting onthe seat, registers with a radial circumferential or annular groove l9provided externally on the reduced part 1 of the base to form a channelfor housing a resilient split ring H which interlocks the cap and baseagainst axial displace ment. The groove 9 is of sufficient depth tocompletely house the resilient split ring H during the assembly of thecap and base. The split ring I i has a normal internal diameter which isless than the external diameter of the part 1 and in order to facilitateassembly of the cap and base, the part 1 is provided with a beveledouter edge I2 for expanding the ring during the movement into assemblyposition. As soon as the cap engages the seat 8, the grooves 9 and IDare in alignment and the ring being free to resume its normal dimensionmoves into the groove I0.

The ring II is formed with undulating upper and lower faces respectivelyl3 and H, the high spots frictionally engaging the walls forming thesides of the grooves 9 and I0 and offering suflicient resistance torotation to insure retention of the parts in adjusted position duringflight.

It is to be understood that if the ring is to be carried by the baseduring assembly then the base will have a groove of sufficient depth andthe beveled edge will be provided on the cap.

I claim:

In a fuse casing, a base having an upper part with an annular bevelededge, a rotatable cap fitting on the upper part of the base, said baseand cap being provided with radial, annular grooves with their depthdimensions normal to the axis of the fuse and which are in register whensaid base and cap are assembled, a resilient split coupling ringdisposed in the grooves and having undulating upper and lower faces anda depth between faces greater than the width of the grooves whereby toresiliently engage both side walls of both grooves and yieldinglyinterlock said base and cap against axial separation, the normalinternal diameter of said ring being substantially the same as thediameter of the bottom of the groove in the base while the normalexternal diameter is such that the peripheral portion of the ring willnormally project without the groove in the base, said groove in the capbeing of sufficient depth to completely house the ring when the same isradially expanded against its own resiliency, whereby the ring may beinitially assembled in the groove of said cap and during assembly of thebase and cap be expanded into the groove in the cap by said beveled edgeto facilitate assembly.

HAROLD G. TOWNER.

